self biasing config modified to reduce effect of xstr param variation

Add a resistor between base and ground and a degen res at the emitter. Along with the emitter current, these will define the collector voltage. Of course, the collector res must also be appropriately sized. The hardware measured gain for this circuit at 1khz was 8.8 and the hand calc'd gain was 8.9. The col vol was meas'd at 2.49V and the hand calc'd vol was 2.5V. The switch at the input is for simulation with EveryCircuit only. To see the DC operating points, open the interactive switch and start the transient analysis. To run the frequency or transient analysis close the switch and run the desired analysis, but first set the source amplitude to the following (for Transient : 100mV, for Freq : 1V). AC gain can be increased significantly by adding an appropriately sized emitter bypass capacitor.

published 8 years ago